1. Field of the Invention
This invention relates generally to knee braces, and more particularly to a hinge appliance having juxtaposed rotating disks with a cam and stop members that prevent rotation when the knee is subjected to a blow from the front and prevent excessive lateral movement between the upper and lower leg and a pair of chambers in the disks filled with a colored liquid that is released upon the disks being subjected to a predetermined lateral force to give a visual indication that the knee joint has received a serious lateral impact and indicates that a replacement hinge assembly is needed.
2. Brief Description of the Prior Art
Athletes and occasional participants in sporting events and recreational such as baseball, football, basketball, volley ball, tennis, running and cycling has often resulted in debilitating injuries, especially to the knee. Often, the injury requires surgical procedures to repair the joint followed by a program of physical therapy.
There are many patents directed toward knee braces and orthopedic appliances, most of which are bulky and/or complicated heavy metal devices that are worn after an injury to immobilize the joint, to allow only a limited range of motion, or to bear the weight of the wearer during the rehabilitation process.
Townsend, U.S. Pat. No. 4,773,404 discloses a multi-axis controlled motion knee orthosis appliance for controlling an unstable knee joint in the sagittal, coronal and transverse planes, comprising femoral and tibial cuffs joined by links which are interconnected to provide a novel mechanical joint wherein camming slots are formed in one of the links with cams disposed on the other link, the slots comprising straight segments and arcuate segments so as to provide approximately 8 millimeters of sliding movement between the femur and tibia, followed by relative rotation about the center of radius of the femoral condyle as the leg is flexed. The tibial cuff is conformed about the boney prominence or shin of the tibia to inhibit rotation of the leg beneath the knee within the brace itself.
Kausek, U.S. Pat. No. 4,966,133 discloses a knee brace for control of ligament instability in all planes having upper and lower cuffs above and below the knee, a polycentric hinge on the lateral side of the knee, and a medial articulation plate on the medial side of the knee. The cuffs are attached to the leg with non-stretchable straps and provide anterior-posterior stability. The medial pivot plate is designed to stabilize the brace on the medial side of the knee and in conjunction with the lateral hinge and a lateral plate provides medial-lateral stability.
Airy, U.S. Pat. No. 5,052,379 discloses a combination brace and exercise apparatus for body joints that is worn by the user in various configurations, including as a splint to hold a body joint immovable, as a brace to permit the body joint to move through a controlled range of motion and as an exercise apparatus to impart resistance to the flexing and/or extension movement of the body joint. The apparatus includes an articulating frame composed of a first frame section connectable to the first limb of a body joint and a second frame section connectable to a second limb of a body joint. The two frame sections are interconnected together by pivot joint assemblies to permit the frame to articulate about a transverse axis corresponding to the anatomical pivot axis of the body joint. A control plate having adjustable stop pins is mounted on the pivot joint assemblies to control the range of motion of the articulating frame. With the control plate in place, various types of resistance units may be employed to resist relative movement of the frame sections in either or both directions about the pivot axis.
Harris et al, U.S. Pat. No. 5,074,290 discloses a floating pivot hinge and knee brace that includes a thigh cuff having inner and outer spaced brace arms adapted to extend along the user's thigh toward the knee, a calf cuff including inner and outer spaced brace arms adapted to extend along the user's calf toward the knee, and floating pivot axis hinges rotatably connecting the inner and outer brace arms of each pair. The hinge is formed by a pair of juxtaposed hinge plates, each having a pivot face in opposition to a pivot face on the juxtaposed plate, with a concave groove in each of the face. A pivot bearing ball is confined between the opposed faces and retained in the concave grooves. A spring, bellville spring, or disk spring biases the hinge plates together when the pivot bearing ball is positioned in the opposed grooves between. The pivot bearing ball provides a floating pivot axis for hinge rotation of the hinge plates and braces relative to each other, the ball and concave grooves allowing the hinge plates simultaneously to slide and pivot relative to each other.
Gildersleeve, U.S. Pat. No. 5,316,547 discloses an orthopedic brace having one or more pneumatic pads mounted thereon to provide secure and comfort able support for the brace when positioned against the body of a user. Each pad includes at least one pneumatic bladder, formed from a flexible skin permanently sealed to enclose a volume of gas therein.
Most of the devices of the type described above are not suitable for use while participating in strenuous exercise or sports activities to prevent an injury from occurring in the first place, and some could even cause an injury to the wearer or other participant if worn during such activities.
Therefore it would be desirable to provide a lightweight disposable knee hinge appliance that may be worn to prevent injuries to the knee joint that supplements the natural resistance of the joint to excessive movement and will alert the wearer when the joint has received a substantial impact.
The present invention is distinguished over the prior art in general, and these patents in particular by a knee hinge appliance having a pair of hinge assemblies that are secured on the leg of a wearer on opposed lateral sides of the knee joint. Each hinge assembly is formed of juxtaposed first and second disks that rotate relative to one another about a transverse axis extending through the knee joint. The first disk has an upper arm secured to an upper strap or band that encircles the thigh just above the knee joint, and the second disk has a lower arm which is secured to a lower strap or band that encircles the lower leg just below the knee joint. The disks have a cam that slides freely in a circular channel with stop members that allow normal flexing of the knee joint but prevent rotation when the knee is subjected to a blow from the front and prevent excessive lateral movement between the upper and lower leg. A pair of chambers in the disks are filled with a colored liquid which is released upon the disks being subjected to a predetermined lateral force to give a visual indication that the knee joint has received a serious lateral impact and indicates that a replacement hinge assembly is needed.